R1-2600046
discussion
On WUS operation in different RRC states
From Nokia
Summary
This Nokia contribution (18 observations/proposals) discusses WUS operation in RRC states for 6GR power savings. It proposes study assumptions and evaluations for duty-cycled WUS in IDLE/Inactive mode for paging and connected mode for PDCCH monitoring, while also exploring broader WUS use cases like SI indication, PDCCH adaptation, and SPS.
Position
Nokia proposes assuming duty-cycled 6GR WUS monitoring with predefined time occasions rather than continuous monitoring, arguing this is necessary to attain UE power benefit given the agreed power model. They propose that WUS monitoring occasions be limited to one time occasion per paging cycle containing one or more continuous WUS monitoring occasions, as increasing monitoring occasions may negatively impact UE power savings. For connected mode, Nokia proposes retaining a basic duty-cycled C-DRX configuration and aligning 6GR WUS monitoring with C-DRX configuration (option 1-1), citing reduced RRM measurement cost in the 6G EE processing state. Nokia proposes studying WUS usage within ACTIVE times (previously deprioritized in NR Rel-19) and extending WUS to support multiple PDCCH monitoring adaptation features including SSSG switching, early termination of PDCCH skipping, and SPS activation/deactivation, while striving to avoid overlapping functionality that occurred in 5G across Cell-DTX, DCP, and LP-WUS.
Key proposals
- Proposal 1 (Sec 2.1.1): For 6GR WUS based power saving, study attainable UE power saving in IDLE/Inactive with paging.
- Proposal 2 (Sec 2.1.1): For the 6GR study of UE operation with OFDM sequence-based DL WUS, assume that 6GR WUS monitoring is duty-cycled, with predefined time occasions.
- Proposal 6 (Sec 2.1.2): Feasibility and the benefit of 6GR WUS indicating the delivery of system information could be studied.
- Proposal 7 (Sec 2.1.2): RAN1 to investigate the benefit of using WUS operation to indicate the applied transmission approach for cell-common signaling.
- Proposal 8 (Sec 2.2.1): From the RAN1 perspective, for the Connected RRC mode operation, a basic duty-cycled based C-DRX mode can be configured.
- Proposal 9 (Sec 2.2.1): For 6GR DL WUS based power saving, study attainable UE power saving in CONNECTED mode when used to trigger ACTIVE time for PDCCH monitoring.
- Proposal 10 (Sec 2.2.1): For 6GR DL WUS study if one or more modes of WUS operation to trigger active time are beneficial.
- Proposal 11 (Sec 2.2.1): RAN1 to study use of WUS in ACTIVE times.
- Proposal 12 (Sec 2.2.2): RAN1 strives for a 6G suite of PDCCH monitoring adaptation features that avoids overlapping functionality.
- Proposal 13 (Sec 2.2.2): RAN1 studies WUS for supporting additional PDCCH monitoring adaptation features, including triggering ACTIVE times with additional indication of ACTIVE time duration, early termination of PDCCH skipping, triggering SSSG switching.
- Proposal 14 (Sec 2.2.2): RAN1 studies the application of WUS to other procedures, e.g. SPS.
- Proposal 4 (Sec 2.1.1): Consider additional synchronization/reference signals prior paging occasion(s) to alleviate the impact of infrequent always-on synchronization signals.
- Proposal 5 (Sec 2.1.1): Feasibility and benefit of 6GR WUS to carry other type of indications, such as SI updated and ETWS/CMAS indication could be considered in 6GR WUS study.